venerdì 20 ottobre 2017

GPS su Android N

Un esempio di uso del GPS su Android N con getione dei permessi. Evidenziate in giallo le parti di codice di gestione dei permessi


---------------------------------------------------
<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.lucainnocenti.gpstest">
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />


    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true"        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>
---------------------------------------------------



---------------------------------------------------
package com.example.lucainnocenti.gpstest;

import android.Manifest;
import android.content.Context;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;

public class MainActivity extends AppCompatActivity implements LocationListener{

    LocationManager locationManager;
    String provider;
    public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

        provider = locationManager.getBestProvider(new Criteria(), false);

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            checkLocationPermission();
            return;
        }
        Location location = locationManager.getLastKnownLocation(provider);

        if (location != null) {

            Log.i("Location Info", "Location achieved!");

        } else {

            Log.i("Location Info", "No location :(");

        }
    }

    @Override    protected void onResume() {
        super.onResume();

        if (checkLocationPermission()) {
            if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
                locationManager.requestLocationUpdates(provider, 400, 1, this);
            }
        }

    }

    @Override    protected void onPause() {
        super.onPause();

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            checkLocationPermission();
            return;
        }
        locationManager.removeUpdates(this);

    }

    @Override    public void onLocationChanged(Location location) {

        Double lat = location.getLatitude();
        Double lng = location.getLongitude();

        Log.i("Location info: Lat", lat.toString());
        Log.i("Location info: Lng", lng.toString());

    }

    @Override    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override    public void onProviderEnabled(String provider) {

    }

    @Override    public void onProviderDisabled(String provider) {

    }

    public void getLocation(View view) {

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

            return;
        }
        Location location = locationManager.getLastKnownLocation(provider);

        onLocationChanged(location);


    }

    public boolean checkLocationPermission() {
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {

            if (ActivityCompat.shouldShowRequestPermissionRationale(this,Manifest.permission.ACCESS_FINE_LOCATION)) {


                new AlertDialog.Builder(this)
                        .setTitle("Permesso GPS")
                        .setMessage("Permesso GPS")
                        .setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                            @Override                            public void onClick(DialogInterface dialogInterface, int i) {
                                //Prompt the user once explanation has been shown                                ActivityCompat.requestPermissions(MainActivity.this,
                                        new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                                        MY_PERMISSIONS_REQUEST_LOCATION);
                            }
                        })
                        .create()
                        .show();


            } else {
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_PERMISSIONS_REQUEST_LOCATION);
            }
            return false;
        } else {
            return true;
        }
    }

    @Override    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
            case MY_PERMISSIONS_REQUEST_LOCATION: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
                        locationManager.requestLocationUpdates(provider, 400, 1, this);
                    }

                } else {

                    // permission denied,

                }
                return;
            }

        }
    }
}

Nessun commento:

Posta un commento